Aromatic carbonate polymers have been end-capped with a variety of end-capping reagents. The most commonly employed family of compounds is the monophenols. The physical characteristics of aromatic carbonate polymers end-capped with the family of phenols are well known. Once the end-capper has been placed in the resin, generally no further chemistry occurs with the end-capping agent.
It has now been found that by using a specifically substituted phenol, further chemistry can be attained. This chemistry succeeds in placing a quaternary ammonium group on the end of the resin chain.